Tube drawing apparatus



March 1944- E. LINDERME, SR

TUBE DRAWING APPARATUS Filed April 22, 1942 2 Sheets-Sheet 1 INVEN] OR EMIL LINDERME SR.

ATTORNEYS March 7, 1944. E. LINDERME, SR 2,343,680

TUBE DRAWING APPARATUS INVENTOR. EMIL LINDERME. SR.

BY M [w w/MA ATTORNEYS.

Patented Mar. 7, 1944 TUBE DRAWING APPARATUS mil Linderme, Sr., Shaker Heights, Ohio, assignor to The Linderme Tube Company,

Ohio, a corporation of Ohio Euclid,

Application April 22, 1942, Serial No. 440,013

7 Claims. (Cl. 205-4) This invention relates to the art of drawing tubes by a cold process wherein tubes are drawn or reshaped by a mandrel and suitable dies, the mandrel preventing the tubes from being crushed or collapsed while being elongated by dies between which the tubes are drawn.

In my United States Patent No. 1,541,424, there is disclosed a tube drawing machine in which provision has been made for loosening the tube from the mandrel as the mandrel and its tube emerge from the die, so as to permit the mandrel to be withdrawn from the drawn tube. The 'tube loosening devices consist, in that case, of a. pair of longitudinally spaced chuck or clutch heads supporting a plurality of radially adjustable rolls adapted to engage the tube and loosen the tube relatively to the mandrel, one of the chuck or clutch heads being bodily revolved in a direction opposite to the direction of rotation of the other chuck head to insure release of the tube from its mandrel. The rolls have a kneading action on the tube and set up suflicient vibration to cause the tube to become loose on its mandrel, so that after the tube has been fully drawn and removed from the drawing bench to the work disassembling begch, the mandrel may bewithdrawn from the tu e.

Due to the fact that the rollers of the tube loosening devices in that case are disposed with their axes parallel or substantially parallel with the axes of the tube and mandrel, a riding or fluting action is imposed by the rollers'on the tube as it is drawn past the rollers, and which manifests itself in the form of scratches or similar imperfections on the surface of the finished tub- I have discovered, however, that I can minimize or eliminate this rlfling or fluting action and produce a drawn tube virtually free from surface defects or imperfections by the simple expedient of mounting the rollers on the chuck" head in such a manner that their axes are disposed at an angle other than degrees to a plane which isnormal to the axes of the tube and mandrel, i. e., a plane normal to the direction of movement of the tube and mandrel.

Where the chuck head lies in such a plane,'the rollers will, of course, have their axes at an angle other than 90 degrees to the chuck head. Expressed in another way, the rollers are so mounted that their axes, if extended, will intersect at an angle less than 90 degrees a vertical plane in which the axes of the mandrel and tube lie.

The invention will be better understood by reference to the accompanying drawings, forming a the limits of the slot. The

part of this specification, and in which like numetals are employed to designate like parts throughout the same.

.rection indicated by the arrows adjoining the line 9 in Fig. 3. p r The. devices are mounted on a framework, consisting of angle uprights I, connected at the .top by means of angles 2, whichsupport'plates or shelves 3, upon which are mounted motors I and 5 for driving the chuck heads to be presentlydescribed. Interconnecting the .front and rear uprights at points intermediate the ends of the latter are angles 8, which support .a shelter. plate 1 upon which the tube loosening devices proper are mounted.

Each of the tube loosening devices comprises a hollow shaftv 8 which is rotatably journalled in a pair of spaced pillow block bearings 9 and Ill rigidly supported onthe plate], the shaft be- .ing rotated by means of the motor 5 through the intermediary of v-belts H and a sheave I2 which is keyed to the shaft 8 at a point between the bearings Band l0.

Threadedly secured to one end of the shaft 8 is a chuck head I3 provided with a hub portion H which abuts the bearing crates with a nut l5 secured to the other end of the shaft and abutting the bearing ill, to restrain the shaft against axial movement" relatively to the bearings 9 and i0.

The chuck head I3 is provided witha pluralityof circumferentially spaced radially ex tending slots or openings IS, in each of which a block I! is mounted, the block being somewhat shorter than the length of the slot l6 so that it is radially adjustable to any position within block is maintained in' radially adjusted position by means of 'a set screw l8, which engages the radially outward surface of the block.

Simultaneous radial adjustment of all of the blocks is effected by means of a rotatable disc l5 which abuts the rear face of the chuck head and. is provided at points spaced inwardly of its periphery with arcuate slots 20, corresponding in 9., and which coopchuck head is rotated in an opposite direction. This causes the rollers-to have a kneading ac-- tion on the tube and sets up suflicient vibration to cause. the tube to become loose on its mandrel. so that after the tube has been fully drawn and removed from the drawing bench to the work disthe slot, and a steel washer II being interposed between the head oi the screw-and the rear surface of the disc is. It will be apparent from this construction that by withdrawing the set-.

screws It and loosening the screws 2 I, and rotating the disc IS, the blocks can be simultaneously radially adjusted to any desired-position within the limits of the openings II, the blocks being then locked in adjusted position in an obvious manner by resetting the set screws and tightening the screws 2|.

The blocks 11 project forwardly from the race of the chuck head and in each of such forwardly projecting portions, a clevis bolt 24 is mounted and retained in position by means of a nut it. The stem of each bolt has its axis extending radially oi the axis of the chuck head and the iurcations thereof support a pin 26 on which is Journalled a steel roller 21. The bolts are rotatably adjustable in the block i1, and are so adlusted that on one chuck head, the rollers 21, in this instance, are disposed with their axes at an angle of approximately degrees to a plane P-P which is normal to the axes or the tube '1" and mandrel M, i. e., which plane is of course,

normal to the direction of movement of the tube and mandrel. Since the chuck head lies in a plane parallel to the plane P-P, the rollers will, of course, have their axes at an angle of 75 degrees to said chuck head. Expressed in another manner, the rollers 21 are so mounted that their axes, if extended, will intersect at angle of degrees a vertical plane in which the axes of the mandrel and tube lie.

0n the other chuck head, the rollers 21 are similarly mounted, but the rollers will be disposed at an angle of 30 degrees to the rollers on the first chuck head, since the chuck heads face each other.

The operationof the tube loosening devices may now be described as follows:

The mandrel M and tube 'I are drawn through a die D mounted on a transverse head H, and as they are thus drawn through the die, the thickness of the tube wall is reduced so that the metal is evenly and slowly crowded toward the rear end of the tube, thus elongating th tube and drawing it out to a desired length. In so drawing the tube while on the mandrel, the walls of the tube receive a pressure which tends to contract the granular or fiber structure of the tube walls and produce a more intimate molecular composition resulting in a strong and tenacious tube.

The drawing of the mandrel and its tube through the die I) causes the tube'T to be compressed about the mandrel M, making it necessary to loosen the tube so that the mandrel may be withdrawn from the drawn tube. This is accomplished by meansoi th tube loosening devices which have been described. As the tube and mandrel pass through these devices in the manner shown in Fig. 3, the rollers 21 exert a slight pressure on the surface oi the tube, thereby decreasing the thickness of the wall to a slight extent, the first chuck head through which the tube passes being rotated in a counter-clockwise manner, as viewed in Fig. 2, while the second assembling bench, the mandrel may be withdrawn from the tube.

Due-to the fact that the rollers 21 are disposed at an angle as described, instead of as in my aforesaid prior patent, the riding or fluting action to which reference has been made, is minimized or completely eliminated and a tub produced which-is virtually free from surface defacts or other imperfections.

It may be further noted that since the rollers are included in the manner described, the rotation of the chuck heads causes the rollers to exert a longitudinal pull on the tube and mandrel, and this pull may be utilized to augment the drawing p'ull eflected by the mandrel.

The angle at which the rollers are disposed may be varied to meet diiferent conditions, a greater angle being used with increasing speeds of the drawn tube.

It is to be understood that the form of my invention, herewith shown and described, is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of my invention, or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. The method of loosening drawn tubing from a mandrel, which method consists in subjecting the tubing to a series of rollers passing circumferentially about the tubing under pressure to decrease the thickness of the wall and partially release the tubing from the mandrel, and then subjecting the tubing to a second rolling operation in which the rollers move in an opposite direction to the first-named rollers and completely loosen the tubing from the mandrel, the rollers being disposed with their axes at an angle of less than to a plane normal to the axes of the tubing and mandrel.

2. The method which consists in moving a tube and mandrel first through a die and then through a series of rollers rotating about the moving tube, and then through a series of rollers rotating in an opposite direction about the tube.

both of said sets of rollers engaging the tubing under pressure, the die and rollers acting to successively decrease the thickness of the wall and loosen the tube from the mandrel, said rollers being disposed with their axes at an angle of less than 90 to a plane normal to the axes of the tube and mandrel.

3. In a tube drawing machine, a die adapted to have a mandrel with the tube thereon drawn through said die to reduce the tube, and sets of tube loosening rolls revolved in opposite directions and adapted to loosen the tube on the mandrel after passing through said die, said rolls having their axes disposed at an angle of less than 90 to a plane normal to the axes of the tube and mandrel.

4. Means for loosening a drawn tube from a mandrel, said means comprising spaced sets of rolls through which the tube and mandrel pass, one of said sets being revolved about the tube in one direction, and the other of said sets being revolved about the tube in the opposite direction, said rolls having their sizes disposed at an angle of less than 90 to a plane normal to said tube and mandrel, and means for varying the radial distance of said' rolls from the axis of said tube.

5. Means for loosening a drawn tube from a mandrel, said means comprising axially spaced revoluble chuck heads, one of said heads being revoluble in a direction opposite that of the other head, said heads facing each other, and each ,of said heads having mounted thereon a plurality of circumferentially spaced rollers, each of which has its axis at an angle-of less than 90 to the face of the chuck head.

6. Means for loosening a drawn tube from a mandrel, said means comprising axially spaced revoluble chuck heads, one of said heads being revoluble in a direction opposite that of the other head, each of said heads having mounted thereon a plurality of circumferentially spaced rollers, each of which has its axis at an angle of less than 90 to the face of the chuck head, said rollers being angularly adjustable relatively to the chuck head upon which they are mounted.

'7. Means for loosening adrawn tube from a mandrel, said means comprising axially spaced revoluble chuck heads, one of said heads being revoluble in a direction opposite that of the other chuck head, each of said heads having mounted thereon a plurality of circumferentially-spaced rollers, each of which has its axis at an angle of less than 90 to the face of the chuck head, said rollers being adjustable ral5 dially of the axis of said chuck head.

EMIL LINDERME, SR. 

